1. Technical Field
The present disclosure relates to projectors, and particularly to a laser projector having speckle-reduction function.
2. Description of Related Arts
Coherent light such as a laser, produces speckle while illuminating a rough surface. Specifically, referring to FIG. 1, reflection from the rough surface 104 is referred to as diffuse reflection. In diffuse reflection, light beams, such as two adjacent light beams 102 and 103, scatter in various directions. The coherent light scattered by diffuse reflection forms an interference pattern in the space away from the rough surface, and a dark and bright granular pattern can be seen by a human eye. The granular pattern is speckle that needs to be reduced for devices using laser projection.